Peugeot 309 auto hatchback.1600cc engine?

When I start car my autodiagnostic orange light comes on and then off and after a miles travel it comes on again and wont go off till I stop and start again , then it stays off till i go another mile if I dont stop it will stay on ,,then it goes off and then will come on again,That oranage light is just to let know I have problem in Fuel Injection or Ignition,,how do I repair it,,AA told me that it wont harm my car running still will just increase my petrol consumption.well I dont need that at these times.